Automatic coating machine



21, 1951 J. A. PAASCHE" 2,565,263

n AUTOMATIC COATING MACHINE Filed May 21, 1949 4 Sheets-Sheet 1 INVENTOR.

ATTORNEYS.

1951 J. A. PAASCHE 2,565,263

AUTOMATIC COATING MACHINE Filed May 21, 1949 4 Sheets-Sheet 2 yam ' ATTORNEYS.

1951 J. A. PAASCHE 2,565,263

AUTOMATIC COATING MACHINE Filed May 21, 1949 4 Sheets-Sheet 5 l g/ yam BY ATTORNEYS.

1, 1951 J. A. PAASCHE 2,565,263

AUTOMATIC COATING MACHINE Filed May 21, 1949 4 Sheets-Sheet 4 INVENTOR.

ATTORNEYS.

Patented Aug. 21, 1951 UN l-TED AT ES, PAT E NT F F I C E AUTOMATICCOATING MACHINE J ns Al Paa'sche, Wilmette,111.

Applicatioii 'May 2'1; 1949; Serial N01 94x72 Claims.

This inventionrelates to airpaintihg machines,

particularly of 'thetype used for applying a coat of paint'; varnish; enamel,- lacquer; or other material, on objects moving.on-a=conveyor-.

In airpaintiri'g an object" with paint, varnish,

enamel, .lacquer, or 'thelikeyit is importa-nt to secure I as even and 4 uniforman application as possible of the' coatihgi material over all irregularlyr shaped parts ofthe'" obaectv When 1 these objects are on a conveyor moving past an-automatically-controlled airpainti'ng station, the securing of such an even and uniform coating depends upon several: interrelated factors. If these objects have irregularly curved, superimposed, and angularly-arrang'ed surfaces, these interrelated factors become verydmportant in securing the desired uniform-and even coating.

The main objects of this invention, therefore, are to provide an improved form of airpainting or coating machine forapplyingpaints, varnishes, enamels,lacquers,- or other materials, to various types and forms of objects of manufacture; to provide an" improved mounting and means for actuating the airbrushes used in'the machines soas'to secure the 'most effective-"coverage of theentire surface of the object's'to becoated; to provide improved mechanism for reciprocating the airbrushes so as to spread'the coatingmaterial completely and uniformly over all'surfaces of eachobject regardless of thecurved, angular, 01"

faces of each object to the airbrushes; to provideimproved means actuatable" by the' conveyor mechanism for disabling theairbfiishes during the turning of the-objects; and 'toprovide an improved machine of this kind which is compact, simple in the const'riictionofits several parts, and highly effective in"operation.

In the accompanying drawings:

Fig. 1 isa perspective" viewof' a preferred machine embodying this" invention constructed for use in applying liquid coatings on various forms of obj ects of manufacture Fig; 2 is a side'elevation 'of thesame;

Fig. 3 is an enlarged vertical, partly sectional, partly elevational View of the overhead 'airpaint ing'mecharfism; taken'oh the liii'E S- fiOfFig. 1;

a 2 Figs: 4 and 5am diagrammatic'views illustrating: howthe reciprocating airbrushes are positionable-so that-the arc of reciprocation substantiallyconforms to-the concave or convex contour ofthe-surfaces-ofi the-objects to be coated;

Figs.--6;7, 8, and- 9 are enlarged fragmentary details=of-the cam and cam trackmechanism whereby object-carrying-platforms are given two l-degree-rotationsin'order; first, to expose'tha opposite surfaces or theobjects to the two-air painting -stations; and second; toreturn the plat--" forms=to-their normal positions. The figures are taken on the lin'e 66 of Fig. 3;

Fige l0 is=an-enlarged-perspective view' ofthe airbrush-supporting bracket for: mounting the-- airbru-shes'=-for the overhead 'airpainting station, which is-most clearly shown-in Figs. 1and3; and 1l= is a blown-upview of-the universalmou-nting whereby the airbrushes are adjustably= attachedorrtheir respective supports.-

, The-hereimshown preferred-embodiment of a coatingemachine-,- constructed in accordance with this invention, comprises a supporting framework or-housing- I 5 w-herew-ith' is associated a conveyor i6 for moving object-supporting platforms l1 througha predetermined path and revolving them inthecourseof-their travel byth'e' action of cam and cam track mechanism'ls' to permit the-ob jectsl9-tobe--coated' on all exposedsurfaces th-rough the'com-bined actionof the airbrushes at an--overhead' paintingstation is and at the two side painting stations zi" and 22', the action of the airbrushes atthe several stations being controlled by' va-lve mechanismsZB arranged alongthe pa'thof the conveyor I 6'.

The housing I I 5-.-is asheet metal construction providing an' airpaintingchamber 25in association-with a--'water-wash'booth- 25 (see Fig. 2): The -latter is equi-pped W-ith-- suitable means for drawing ofi the 'overspray and-washing the particles=-or coati=ng material 'from -the air currents and-directing them intoa settling Tlre paintingr-or'- atomizing chamber 24 is open a't -the'front and-at the ends thereof, the hous ing 'l5 being provided-with openings 26 and -2'I through which the objects 19" on the platforms- Ii enter and exit from the chamber 24.

The conveyor i6" comprises tracks 28 upon whieh travel-the link-belts '29 which are spanned by andtwheretoare'connected plates 30, whereon aresupDortedthe rotatable platforms 1 1. A suit-- able sourceof-pewer, preferably an electric motor (not shown) is *provided-ior operating the con,- veyor l 6;

' The--traoks 2fl are supported alongthe upperopposite edges of a V-shaped frame 3|, the base of which provides a support for the rails of the cam and cam track mechanism IS. The link belts 29 are, of course, provided with suitable rollers 32 which travel on the tracks 28. The plates 30 are secured at their ends to the links 29 by angle brackets 33.

Each of the platforms I1 is secured to the upper end of a shaft |1.| supported on a roller bearing 34 mounted on a plate 30. At the lower end of the shaft |1.| is secured an arm 35 supporting rollers 36 and 31 at its opposite ends, which rollers travel along the hereinafter-described cam tracks and effect the rotation of the platforms H, as will be subsequentl explained.

Each of the platforms I1 is provided with' prongs or shoulders 38 (see Fig. 1) for holding an object I 9 in place durin its travel through the airpainting chamber 24.

The cam and cam track mechanism |8, comprises the aforesaid roller-mounting arms 35 and a pair of rails 39 which are coextensive with the conveyor |6. These rails 39 provide a guideway 40 for the rollers 36 and 31. At two points along their upper sections the rails 39 are intersected by a plate 4! and a pawl 42 which coact to form transverse branches 43 to the guideway 40 and into which the rollers 35 and 36 are diverted, during the movement of the conveyor IE, to effect the desired rotation of the platforms l1. One plate 4| and pawl 42 are located about mid-way of the painting chamber 24 and between the airpainting stations 2| and 22. Another plate 4| and pawl 42 are located adjacent the left-hand end of the painting chamber 24 near the exit 21.

The plate 4| for each of these diverting branch guideways 43, is fixed whereas the pawl 42 is pivoted at 44 and urged by a spring 45 so that its cam surface 46 extends across the guideway 40. Coacting shoulders 41 on the plate 4| and pawl 42 position the pawl 42 so that its cam surface 46 is positioned to direct a roller into the branch guideway 43.

Figs. 6, '7, 8, and 9 show the consecutive relationships of the roller-supporting arm 35 and a retractable pawl 42 as they effect the turning of the platforms IT at two points during their travel through the painting chamber 24.

The objects |9 which, in the course of time, may be carried by the platform I! for air coating, of course, will be of varied shapes. The objects herein-shown are sewing machine heads. As is apparent from the drawings, each comprises a base 41 and a vertically-s aced arm 48. These parts present horizontal and vertical surfaces that have to be coated by the combined functioning of the airbrushes at the painting stations 20, 2|, and 22. Moreover, some of the surfaces are both convex and concave, which presents a special problem in uniform and even coating.

The airbrushes for the three airpainting stations 20, 2|, and 22 are of the same form, construction, and operation as those set forth in Paasche Patent No. 2,401,503, issued June 4, 1946.

For the overhead airpainting station 20 a bracket 49 supports three airbrushes 50 somewhat inwardly of the conveyor entrance 26.

The bracket 49, as most clearly shown in Fig. 10, comprises rods adjustably supported in clamps 52 carried by an arm 53 which is secured to a rod or post 54 telescopically clamped in a tube 55. A plate 56, at the inner end of the tube 55, provides for attachment of the bracket 49 to the side of the housing l5. An airbrush 56 is adjustably supported on each of the rods 5| by a universal clamp 51 (see Fig. 11). Such an arrangement of the rods 5 I, the telescoping members 54 and 55, and the clamps 51, in addition to the spray-adjusting construction of the airbrushes themselves, permit the airbrushes 56 to be so focused on the objects l9 as to coact with the airbrushes for airpainting stations 2| and 22 in securing the most effective results in the coating of the objects l9.

The airbrushes 50 for the overhead airpainting station 20 are connected by flexible tubes 58 to an air line 59 and to a coating material supply line 60 (see Fig. 1). The air line 59 is provided with a valve mechanism 6| (see Fig. 3) located adjacent the path of travel of the conveyor l6 and also has interposed therein an air conditioner 62 for extracting oil, Water, and solid particles from the air. The coating supply line 60 leads to a source 63 of coating material (see Fig. 1).

The two side airpainting stations 2| and 22 are practically identical. Each includes a pair of automatic airbrushes 64 and 65, respectively, of the type shown in the aforesaid Patent No. 2,401,503, mounted on crank rods 66 and 61, respectively, connected to a three-piece rock shaft 68 journaled on standards 69 parallel with the path of the conveyor I6. At its right-hand end the rock shaft 68 is connected by a pitman 10 to a stroke-adjusting disk crank 1| which is driven by a motor 12.

The automatic airbrushes 64 and 65 are adjustably secured to the respective crank rods 65 and 61 by clamps, such as shown at 51 in Fig. 11, and as most clearly shown in Fig. l, are spaced apart in the direction of the travel of the conveyor l6 with their atomizing axes converging on an object I9 to be coated. Thus, one of the pairs of airbrushes 64 and 65 has its spray directed toward the advancing surface of an object 19, whereas the other airbrush of each pair has its spray directed toward the trailing surface of the object. The airbrushes for painting station 2| coat one side of an object l9, whereas the airbrushes for painting station 22 coat the opposite side of the object, the object being turned degrees between the two stations, as hereinbefore explained.

By reason of the universal clamps 51 (see Fig. 11) the airbrushes 64 and 65 may be not only angularly-dispcsed with respect to the object 59 to be coated, but also may be set concentrically of the axis of the rock shaft 68 or eccentric-ally forwardly or rearwardly of said rock shaft axis. This makes possible the positioning of the airbrush orifices so that they will travel through arcs substantially parallel or concentric with the concave or convex character of the surfaces of the object l9 to be coated (see Figs. 4 and 5). Thus, the distance between the atomizing orifices and the surfaces of an article i9 remains practically constant throughout the reciprocating movement of the sprays. This insures a more even coating of the material on the objects than has heretofore been possible.

The airbrushes 64 and 65 are connected by suitable flexible tubing 13 to air lines 14 and '55, re spectively, and to the coating supply line 69.

The air line 14 has a valve mechanism 16 and the air line 15 has a valve mechanism 11, of a type more clearly shown at 6| in Fig. 3, both arranged adjacent the path of the conveyor I The air lines 14 and 15 are connected to a source of air pressure through suitable air conditioners 16 and 19, respectively.

Associated with the respective valve mechacumen following-Somat c I 9 beyond; the eflectivesrea'clriof painting station: 21; the: second"; pawl 42-3 coacts with: theerollersson an :arm 13 5 to: againirotateithe' supportingizplatform 180 :degrees; thereby'restor; ingsit toiritsinorma'l ipositionfor:receiving-another object; as? such: platform again approaches the entraIIce' ZS-I to :thei'airpainting"chamber. 24;? This second:- turningiofreach platform: I 1 occurs: asith e platform-approaches tlfeexit ropening2 I from the paintingchambertfli During the travel of ithe i'conveyor I6",:-the:aair:- brushes 6 l? and; 6 5 are: being constantly" reciprocated'nptandsdo'wnso: thatthe taxes of the fsprays are? traversing; an:- arc substantially equal? to the verticaliriimensiomofzth'esobjectszl9.? Thissensures aimevemandiiuniform' application of the:- coating whenitheiohjects 'arerbieing rotatednlo'etweemtliese' paintingrstations and beyondntlietlattera Theatop'eration of thisreferred-embodiment 'of ascoatingnmachine is substantially asafollows:

Objects I 9-" are: placed? one a-t a" time rupon the platforms: I I as they come into lforizontal'position at'thevright-handrend of tlrerhousing zl 5 One-at artime 'theyare suitably-removedfrom the plat-- forms after painting and after they: have passed through-thev eXitiZJ frOm-the paintingichamber '24.

As: an object I9 approaches ethev overhead fair.- painting station 29;: the: lever 80,-whicheconti ols the='-valve mechanism SI for the air'line'leading'f'to the-r=airbrushesr 50; is relea'sedand the airbrush-es 5! apply material .onithe' morer'ora less horizontal surfaces- 01: the obj ect; I9; Asrwillbe mosti'clear' from Fig; 3, other outsiderairbrushes 50vare positi'oned and adjusted particularly to coat-the -base .1-; and especially that portion lyingrdir'ectlv'um" derathe head=48r The m'iddle airbrush- 5fl'=is po sitioned and adjusted to especially; coat "the" upper sn-rface ofthe head 48; Of. necessity; thispaint supplements to. an extent the paint fromzthez'out side :airbrushess How much: this iSzSOgYOf course; depends upon the'adjustment .of :thewalve "mech; anism for the middle airbrush;

As an object approaches :the respective-side airpainting: stations 2 I 1 and 22; the"'-leve1's'-8I and-"2% control-l-ingthe air-line valvemechanismszforthe' pair of-airbrushesfid and"65; arereleased: The left-hand airbrushes'fifl and- B5 directYtheiYpai1rt primarily against the advancing? :surfac'esl of the objects; whereas the right-hand? airbrushess 64' and 65 direct: their 'paint'primarily '"against the trailing surfaces of the-"objects -'I 9.

As an object [9 movesrbeyondstheieffective" reach of: theeirpaintingstation'iz I therrollersfi on the arm 35; connected to the shaft". I 1.1 ioff'vth'e platform .I l r supporting:- that tob j ect; contacts? the camrsurface' 4 fi'wofthe' pawl ,"42 :(see Fig: 6) This forces ithearollerifito'move into the'ibranch 43; as" shown'inFig-s: 7,- With: as consequent turningroi theiplatform'eo degreest The-.i'continued' move= ment of" the conveyor '5 I 6 requires theiiarm 35" to' continue its swinging; action;therebwcontinuingtheirotation of the platform: I! and causingiithe' trailing: roller 31 to approach: thei-guidewayfl lfl beyondthe=retractable pawli42ias sh'ownFinl? ig;8 The advance of'the conveyor being unchecked,itlfe rolleri3fi 'moves'out of theebranch guidewayw3 "and retracts thetpawl' 421agaihstthe action of the spring'45; as shown inFig; 9. Thereupon; thear= ticle' I 9 has been turnedfa full' l80i'd'e'gree's 'sof-th'at theiopposite'face thereof 'isin positionto be coated byrthe airbrushesi-at painting :statiomZZ; v I

As 'eachnbj ect passes beyond the efie'ctive reach oti the "1 second '1 side paintingistatiorr 2'2 which is practically simultaneous: with-b the passing: of a" material'ontheobjects I9;

Ifiass thercasef of the": particular" obj cots l9: hereintslsiown; therside surfaces -aremore or less convex; the: airbrushesfiii and 65 may'b'esoratljust ed'iionrth'e' respectivecrank rodsz-GG and 61 th'at'the' atomizing; orifices; are f-rearwardly of the Y axis of therroclc shaft fiil-s Thus; as diagrammatically shown inlFfigsbithe airbrushes Gland-65 move through arcs whichr: are more or less" concentric the arcuate character of the: surface being airpaintedi This means? that the distance from the? atomizing sorifices to the: surface of theobje'ct is:- substantia'llyi the same throughout the total range. of ir'eciprocati'oniof I the ax'e's of 1 the sprays.

If; at: other? times the'objects to be airpainted havesa concave surface, the airb'rushes 6'4 and'65 can be adjusted fon the respective crank' rods 6'5 andtfil forwardlvof the axis of the crank shaft 681 Thus;.ass:dia:grammatically shownin Fig;- 4, the airb'rushesswould bemoving th'rcughlarcs substantially: concentric: with I the concave" character of the surface*being airpaintedi- Here,- also, the dis= tances between theatomizing orifices and thesurfaces: beingairpainted are practically constant throughout th'e range of reciprocationof theaxes ofthe spraysi Suchadjustment of theairbrushes further ensures securing an even and I uniform spreadofthe coatmgI It willb'e understood, ofcourse, that inaddition toauj-u'stingtl'ieangularity of f the 'airbrushes 50}643 and "65 with respect to theobject'being airpaifited thech'aracter of each spraycan be 2.1 teretl by an adjustment of the airbrush valve mechanism; as:set'-forth in the aforesaid'Patent No 2 40155035 Altl'iougl'i but one specific embodiment ofthis invention lias been 1 herein 1 shown and described, it wi-ll be understood-that details of the construction shown may ide alteredor omitted with'outdeparting from thespirit of the invention as defined byth'e following claims.

I claim:

1i Ifr a machine *for air coating objects; the combination of asupporting framework, air" brushes arran'ged to" provide two painting statl'on's'; an'endless'conveyor for moving'objects past saidpainting stations, platforms rotatably mountedonsaidcomeyor for supporting articles to -be moved past-said painting stations; crank means on each 1 of saidplatforms for causing rotation thereof, means on said framework for actuating said crank means, said actuating means beingliicated ata point in theinterval of passage between said painting stations and a'second actu-' atin'g means on said framework positioned at a point beyond 'the second painting station passed by-sai'd' 'nbiiectsjsaid actuating means successively turning" each" of-s'aid platforms degrees: be tween? sald painting" stations and again beyond 7, said second painting station whereby the opposite sides of each object are successively exposed to the painting action of said stations and each platform is returned to its initial position for subsequently receiving another object, valve mechanisms arranged along the path of said conveyor for separately controlling the airbrushes for each of said painting stations, and means on said conveyor for actuating said valve mechanisms so as to disable the respective air-brushes when said platforms are being turned.

2. In a machine for air coating objects, the

combination of a supporting framework, airbrushes positioned at spaced points, a conveyor for moving objects past said airbrushes, platforms for supporting articles to be coated rotatably mounted at intervals on said conveyor, a cam guideway paralleling said conveyor and having a transverse branch intermediate said airbrushes, a cam connected to each of said platforms and adapted to contact said guideway to normally hold said platforms against rotation, a pawl arranged adjacent said transverse branch and normally positioned to engage the advancing edge of each of said cams and divert them into said transverse branch so as to initiate the turning of the respective platforms, said pawl being subsequently engagea'ble with the trailing edge of each cam so as to successively effect a 180-degree turning of said platform and retraction of said pawl incident to the uninterrupted movement of said conveyor.

3. In a machine for air coating objects, the combination of a supporting framework, airbrushes positioned at spaced points, a conveyor for moving objects past said airbrushes, platforms for supporting articles to be coated fixed on shafts rotatably mounted at intervals on said conveyor, a cam guideway paralleling said conveyor and having a transverse branch intermediate said airbrushes, an arm on each of said platform shafts having a roller journaled at each end, said rollers engaging said guideway to normally hold the respective platforms against rotation during their travel through said chamber, and a retractable pawl arranged adjacent said transverse branch and normally positioned to engage the roller on the advancing end of said arm and divert it into said transverse branch so as to effect a 90-degree rotation of said platform, said pawl subsequently engaging the roller on the trailing end of said arm so as to complete the 180-degree rotation of said platform, said pawl being retractable by the pull of said trailing roller as said advancing roller re-enters said guideway incident to the uninterrupted movement of said conveyor.

4. In a machine for air coating irregularly shaped objects, the combination of a moving, rotatable platform for supporting articles to be coated, means for moving and rotating said platform, a rock shaft mounted in spaced relationship to said platform, an airbrush supported on said shaft in position to direct a coating onto said object, means for actuating said shaft whereby the axis of said airbrush orifice is shifted back and forth with respect to the surface of the object being coated, and means for securing said platform against rotation during the coating operation.

5. In a machine for air coating irregularly shaped objects, the combination of a moving, rotatable platform for supporting articles to be coated, means for moving and rotating said platform, a rock shaft mounted in spaced relationship to said platform, an airbrush supported on said shaft in position to direct a coating onto said object, means for actuating said shaft whereby the axis of said airbrush orifice is shifted back and forth with respect to the surface of the object being coated, and for adjustably positioning said airbrush on said shaft so as to locate said airbrush orifice concentrically or eccentrically of the center of said shaft in position to direct a coating onto said object, and means for securing said platform against rotation during coating of said objects.

6. In a machine for air coating objects, the combination of a supporting framework, a moving, rotatable platform for supporting articles to be coated, means for movin and rotating said platform, a rock shaft mounted in spaced relationship to said platform, a crank rod offset from said rock shaft, means for actuating said rock shaft, means for adjustably positioning an airbrush on said crank rod so as to locate the discharge orifice concentrically or eccentrically of the center of said rock shaft in position to direct a coating onto said object and means for moving said platform transversely of the axis of the'orifice of said airbrush, means for preventing rotation of said platform in the effective range of said airbrush.

'7. In a machine for air coating objects, the combination of a conveyor arranged to move objects through a predetermined path, platforms rotatably mounted on said conveyor for supporting objects to be coated, means for rotating said platforms, a rock shaft journaled on an axis parallel to the travel of said conveyor, a pair of airbrushes mounted on said rock shaft and spacedapart from each other axially of said shaft with their respective discharge orifice axes converging toward the object to be coated whereby one of said airbrushes coats the advancing surface of the object and the other airbrush coats the trailing surface of said object, means for actuating said rock shaft, and means for securing said platforms against rotation in the painting range of said airbrushes.

8. In a machine for air coating objects, the combination of a supporting framework, a conveyor for moving objects along a predetermined path, platforms for supporting said object rotatably mounted on said conveyor, a rock shaft journaled on said housing with its axis parallel to the travel of said conveyor, means for actuating said shaft, pairs of airbrushes mounted on said rock shaft to provide two air painting stations spaced apart axially of said shaft with the airbrushes at each station being positioned so that the axes of the discharge orifices converge toward the object to be coated, coacting means on said framework and said platforms for effecting'a -degree rotation of each of said platforms at a point in the interval of passage between said stations, means for securing said platforms against rotation during air coating, valve mechanisms controlling the airbrushes for each station located adjacent the path of said conveyor, and means on said conveyor positioned relative to each of said platforms for actuating said valve mechanisms so as to disable said airbrushes during the rotation of said platforms.

9. A system for air coating moving objects, which comprise a painting chamber wherein pairs of airbrushes are arranged to constitute two painting'stations, a conveyor for moving objects through said chamber past said stations, means for rotating each of said objects at a point in the interval of travel between said stations and at a point after the coating of each object is compieted, and means for substantially preventing rotation of said objects when in the range of said painting stations.

10. A system for air coating moving objects, which comprises a painting chamber wherein pairs of airbrushes are reciprocatingly mounted in said chamber and arranged to provide two painting stations, each airbrush having an orifice directed at the moving objects and in converging relation with respect to the paired airbrush, means for mounting and reciprocating said airbrushes so that the axes of the orifices are shifted back and forth across the surface of the object to be coated, a conveyor for moving objects i ii said airbrushes and rotating each of said objects at points intermediate said stations and after the coating of each object is completed.

- JENS A. PAASCHE.

REFERENCES CITED The following references are-0f record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,124,858 Caruso et a1 Jan. 12, 1915 2,069,844 Paasche Feb. 9, 1937 2,072,948 Geifs Mar. 9, 1937 2,261,138 Bullerjohn Nov. 4, 1941 2,342,375 Shurley Feb. 22, 1944 2,373,604 Schweitzer Apr. 1'0, 1945 

